Google ignores common words and characters such as "where" and "how", as well as certain
single digits and single letters, because they tend to slow down your search without improving
the results. Google will indicate if a common word has been excluded by displaying details on
the results page below the search box.
If a common word is essential to getting the results you want, you can include it by
putting a "+" sign in front of it. (Be sure to include a space before the "+" sign.)

For example, to search for "Using the NTFS File System", use:
Using +the +NTFS +File +System